bryson



March 10, 1964 J. L. BRYSON BOBBIN CONTROL FOR SEWING MACHINES 2 Sheets-Sheet 1 Filed June 29. 1961 27 FIG. 3

INVENTOR. J. L. B RYSO N ATTORNEY March 10, 1964 Filed June 29. 1961 J. L. BRYSON BOBBIN CONTROL FOR SEWING MACHINES 2 Sheets-Sheet 2 INVENTOR. J. L. B RY S O N ATTORNEY United States Patent Ofiice 3,124,088 Patented Mar. 10, 1964 3,124,ll88 EEGEBIN CGNTRQL FGR SEWING MACHINES James L. liryson, Clifton, NJ assignor to Bryson Manugacturing Co., lino, (Ciifton, N.J., a corporation of New ersey Filed June 29, 1961, Ser. No. 120,637 2 Claims. ((1 112-219) This invention relates to electric sewing machines having bobbins for stitching material fed through the machine in a given direction, the bobbin for example being disposed at one side of the material and supplying a thread to form stitches with a second thread fed by a needle at the opposite side of the material. The object of this invention is to assure the machine being automatically stopped upon breaking of the thread, which, in practice, frequently occurs.

Pursuant to the invention, stopping of the machine is effected by cutting off the power instantly upon the occurrence of a break in the thread. Accordingly, the invention is adapted for use in plants having large numbers of such sewing machines, enabling an operator to promptly locate the machine with the broken thread (such machine will have stopped its operation) enabling the operator to rapidly repair the broken thread and reset the machine for continued operation. The invention thus assures a continuation of operation of the machine with a minimum loss of time and supervision and automatically assures the operation of the machine only while the thread is continually and properly being stitched into the material, discontinuing such operation automatically when a break in the thread occurs.

In the drawings,

FIG. 1 is a partly fragmentary perspective view of a bobbin control unit embodying the invention,

FIG. 2 is a vertical, elevational sectional view thereof, taken at line 22 of FIG. 3, showing the unlatched position of the parts of a control unit of this invention which discontinues operation of the sewing machine controlled thereby on a break in the thread,

FIG. 3 is a partly sectional bottom plan view, taken at line 3-3 of FIG. 1,

FIG. 4 is a partly fragmentary vertical sectional view, corresponding with FIG. 2, showing the parts in latching position, permitting continued operation of the sewing machine,

FIG. 5 is a bottom plan view taken at line 5-5 of MG. 4,

FIG. 6 is a fragmentary perspective view of a head portion of a sewing machine and associated parts to which a unit embodying the invention is shown secured,

FIG. 7 is a similar view, showing the securing of said unit at another position thereon, and

FIG. 8 is a vertical elevational, partly sectional view, showing the tripping of the latch means of this invention to open the power circuit of the sewing machine upon breaking of the thread.

As shown in the drawings, the bobbin control unit of this invention is adapted for use on a sewing machine having a head portion it (FIG. 6) electrically driven to reciprocate (as at 17), the needle 11 which feeds a second thread 12 into stitching engagement with a bobbin thread 13 (FIG. 8) through material 14 (passed through the machine in the direction of arrow 22), defining the stitches therein while the bobbin thread 13 remains unbroken, in the normal operation of the machine.

As above noted, the control unit of this invention is designed to prevent the continuation of operation of the machine when (as in FIG. 8) the bobbin thread 13 is broken, as follows:

In operation of the sewing machine, the needle bar 16 is reciprocated to feed second thread 12 (arrow 17, FIG. 6) and the bobbin 18 complementarily feeds the thread 13 in cooperation with other parts of the machine, such as the feed dog 19 (FIG. 8) for advancing the material 23 in the machine on the table at the stitching station thereof under the presser foot 21 and in the direction of the arrow 22.

The machine is electrically operated, as is well known in the art. Pursuant to the invention, first and second electric contact members 24 and 25 (FIG. 3) are provided, the first contact member 24 being secured to the free end of the elongated rod 26 axially slidably positioned in casing 27 and preferably extending out of the casing for resetting as below described. The rod 26 is urged in the direction of the arrow 28 by suitable means such as spring 29 to thus urge the contact end 24 of said rod toward the second contact element 25. When elements 24, 25 are closed (FIG. 3) the circuit is thereby completed, as for example, through the wires 30, 31 (FIG. 1), through a solenoid or other control member to thereby open the sewing machine operating circuit. Pursuant to the invention, the FIG. 3 condition is attained upon breaking of the bobbin thread, in the following manner. The free end 24 of elongated rod 26 is in normal operation of the machine, disposed (FIG. 5) in spaced relation to the second contact 25 and the rod 26 is held latched against further movement responsive to spring 29, by latching means generally indicated at 35 in FIG. 5, which may comprise a shaft 36 rotatably journalled in said casing in spaced parallel relation to the elongated rod 26 and the latch element 37 fixed to the shaft 36 as for example by the means 38 (FIG. 4). Latch element 37 is preferably rotated against rod 26 by spring or other means 39 (FIG. 4). The rod 26 and the latch member 37 are provided with complementary shouldered portions 41, 42, FIGS. 3 and 5, such that upon engagement of said shouldered portions (FIGS. 4 and 5) the shaft 26 will be held spaced from the second contact 25. Upon rotating of latch member 37 (FIG. 2, arrow 47) to move its shouldered portion 41 away from the rod 26, the rod 26 will be no longer held by the latch means 37 and will move responsive to the spring 29 to close the contacts 24, 25 (FIG. 3) and thus open the sewing machine circuit. Movement of the latch member 37 against the tension of spring means 39 and in the direction of arrow 47 (FIG. 2) results from movement of arm 45 secured at one end to said shaft 36 (to which member latch on 37 is secured) on breaking of the bobbin thread. The opposite free end of arm 45 is angularly directed as at 46 (FIG. 7) to present a wide surface disposed at the stitching station of the machine, normally urged in the (full line position of arm 45) direction of the arrow 43 (FIG. 4) by the spring 39 urging the member 37 against (FIGS. 4 and 5) shoulder 42 of shaft 26. The full line position of the arm 45 shown in FIG. 4 is its normal position responsive to the urging of the spring 39, which continues as long as the free end 46 of the arm bears against the thread 12 (FIG. 7) with the latter disposed in the generally vertical direction while the thread 12 is properly stitched with the bobbin thread 13. Upon the occurrence of a break, however, in the bobbin thread (FIG. 8) continued movement of the material 14 in the direction of the arrow 22 will carry the needle thread 12 with said material angularly and thereby will move the end 46 of the arm 45 in the direction of arrow 40 (FIG. 2) and rotate arm 45 to the dotted line (FIG. 4) and full line (FIG. 2) position. This rotation of arm 45 moves the latch member (35, FIG. 2, arrow 44)) out of engagement with the shaft 26 whereupon the shaft 26 will move (arrow 28, FIG. 3) and contacts 24 and 25 will close, thus completing the circuit of a control unit wired to wires 30, 31 (FIG. 1) and thus the electric power of the sewing machine will beimmediately discontinued. The operator may readily "reset the parts when the break of the bobbin thread has been repaired, by simply moving shaft 26 to the FIG. 5 position until the latch element 37 snaps intoengagement with the shoulder 42 or shaft 26. The end 46 of arm 45 is disposed at the stitching station (FIG. 7) of the machine to bear against the thread 11 while the parts are latched (FIGS. 2, and 5) as above described. As shown in- FIGS. 4. and 5.1 provide means for adjusting the latched position of arm 45 so that (FIG. 3) it will then be disposed at precisely the desired point to suit the requirements of the particular application involved. To that end, pursuant tothis invention, I provide a latch arm adjusting screw 54 which passes threadedly through the wall of casing 27 in line with the latch element 37 and said screw 54. is looked as at 55 at the desired position so that the free end 56 thereof will stop and limit the movement of member 37 downwardly in the latching position of'the parts. It will be appreciated that the parts are of relatively small dimensions and that, in practice, the adjustment thus attained precisely adapts the device to various applications wherein the free end 46 of arm- 45 is to be disposed atslightly diiferent positions depending on requirements. The shoulder 41 of latch element 37 holds rod 26 in latched position in all cases in the FIG. 2 position of the parts, While the latch arm adjusting screw 54 thus determines the precise extent of downward movement of member 37 and thus the position of arm 45 and of its end 46 when the parts are latched (FIG. 5). It Will be appreciated from the foregoing that the device is relatively sturdy and practical in manufacture and use and may be reset readily, rapidly and eificiently.

I claim:

1. A control unit for a sewing machine having a stitching station provided with a threaded needle member for cooperation with a bobbin thread for stitching a length of material fed through said machine, said control unit being adapted for opening the electric power circuit for said machine on breaking of the bobbin thread, said control unit comprising a casing adapted to be secured to thecasing and extending exteriorly of the casing to enable manual grasping of the rod to shift the rod, a first electric contact member secured to the free end of the said rod, a second electric contact member secured in said casing in line with the axial movement of the free end of said rod, spring means urging said rod for movement axially thereof to carry the first contact member into contact with said second electric contact member, a latch member mounted in the casing for movement in a plane transverse to the axis of said rod, complementary portions on the latch member and rod for movement of the latch member to a position in latching engagement with the rod, holding the rod to prevent movement thereof against the second contact member, an elongated arm secured to said latch member at one end for movement therewith in a given direction, theffreeendvof said arm being disposed at the stitching station of said machine, means urging the said free end of the arm against the thread passing from the needle and into the material fed through the machine and the latch member into latching engagement with the rod to latch the latter so that the free end thereof will bespaced from the second contact, so that on breaking or" the bobbin thread, the free end of the arm will move with the material, and said latch member will thereby be moved out of latching engagement with the rod, and the latter will move into closed contact with the second contact member.

2. In a bobbin control unit for sewing machines as set forth in claim 1, said complementary portions comprising a shouldered portion on said latch member and a complementarily shouldered portion on said rod.

References Cited in the file of this patent UNITED STATES PATENTS 1,281,095 Taylor Oct. 8, 1918 2,643,305 Mansson June 23, 1953 2,674,214 Schwartz Apr. 6, 1954 2,747,039 Vossen May 22, 1956 2,747,040 Vossen May 22, 1956 2,796,035 Bryson June 18, 1957 2,921,546 Vossen Jan. 19, 1960 

1. A CONTROL UNIT FOR A SEWING MACHINE HAVING A STITCHING STATION PROVIDED WITH A THREADED NEEDLE MEMBER FOR COOPERATION WITH A BOBBIN THREAD FOR STITCHING A LENGTH OF MATERIAL FED THROUGH SAID MACHINE, SAID CONTROL UNIT BEING ADAPTED FOR OPENING THE ELECTRIC POWER CIRCUIT FOR SAID MACHINE ON BREAKING OF THE BOBBIN THREAD, SAID CONTROL UNIT COMPRISING A CASING ADAPTED TO BE SECURED TO THE MACHINE AT THE STITCHING STATION, AN ELONGATED ROD SLIDABLY SECURED IN SAID CASING FOR AXIAL MOVEMENT THEREOF IN SAID CASING AND EXTENDING EXTERIORLY OF THE CASING TO ENABLE MANUAL GRASPING OF THE ROD TO SHIFT THE ROD, A FIRST ELECTRIC CONTACT MEMBER SECURED TO THE FREE END OF THE SAID ROD, A SECOND ELECTRIC CONTACT MEMBER SECURED IN SAID CASING IN LINE WITH THE AXIAL MOVEMENT OF THE FREE END OF SAID ROD, SPRING MEANS URGING SAID ROD FOR MOVEMENT AXIALLY THEREOF TO CARRY THE FIRST CONTACT MEMBER INTO CONTACT WITH SAID SECOND ELECTRIC CONTACT MEMBER, A LATCH MEMBER MOUNTED IN THE CASING FOR MOVEMENT IN A PLANE TRANSVERSE TO THE AXIS OF SAID ROD, COMPLEMENTARY PORTIONS ON THE LATCH MEMBER AND ROD FOR MOVEMENT OF THE LATCH MEMBER TO A POSITION IN LATCHING ENGAGEMENT WITH THE ROD, HOLDING THE ROD TO PREVENT MOVEMENT THEREOF AGAINST THE SECOND CONTACT MEMBER, AN ELONGATED ARM SECURED TO SAID LATCH MEMBER AT ONE END FOR MOVEMENT THEREWITH IN A GIVEN DIRECTION, THE FREE END OF SAID ARM BEING DISPOSED AT THE STITCHING STATION OF SAID MACHINE, MEANS URGING THE SAID FREE END OF THE ARM AGAINST THE THREAD PASSING FROM THE NEEDLE AND INTO THE MATERIAL FED THROUGH THE MACHINE AND THE LATCH MEMBER INTO LATCHING ENGAGEMENT WITH THE ROD TO LATCH THE LATTER SO THAT THE FREE END THEREOF WILL BE SPACED FROM THE SECOND CONTACT, SO THAT ON BREAKING OF THE BOBBIN THREAD, THE FREE END OF THE ARM WILL MOVE WITH THE MATERIAL, AND SAID LATCH MEMBER WILL THEREBY BE MOVED OUT OF LATCHING ENGAGEMENT WITH THE ROD, AND THE LATTER WILL MOVE INTO CLOSED CONTACT WITH THE SECOND CONTACT MEMBER. 